Mainframe computers are labor intensive programming environments. Mainframe computers run jobs that call procedures or procs to perform certain functions. Each proc may include parameters or parms that operate as variables. Each job typically includes a proc and one or more corresponding control cards.
Image screens, which are typically text-based, user interface screens, operate as user interfaces with application programs. Programming image screens is a labor intensive effort as the software coding used to create the image screens uses a lengthy macro language. Even though certain display software libraries have been created over the years to simplify displaying image screens on different display terminals, programming each customized image screen using lengthy macro language software coding is still time consuming and labor intensive. In addition, programming image screens generally requires a skilled programmer to perform the coding.
Information Management System is a database management system available from International Business Machines (IBM). Message Format Services (MFS) is a library of software modules that are usable by IMS macros to produce image screens. As with other mainframe computer software packages, creating image screens by programming using MFS is still labor intensive and time consuming.